<s>
Back	B-Operating_System
to	I-Operating_System
My	I-Operating_System
Mac	I-Operating_System
was	O
a	O
feature	O
introduced	O
with	O
Mac	B-Application
OS	I-Application
X	I-Application
Leopard	I-Application
(	O
10.5	O
)	O
that	O
uses	O
Wide-Area	O
Bonjour	B-Application
to	O
securely	O
discover	O
services	O
across	O
the	O
Internet	O
and	O
automatically	O
configure	O
ad	O
hoc	O
,	O
on-demand	O
,	O
point-to-point	O
encrypted	O
connections	O
between	O
computers	O
using	O
IPsec	B-Protocol
.	O
</s>
<s>
The	O
current	O
version	O
of	O
the	O
feature	O
requires	O
users	O
to	O
have	O
iCloud	B-Application
set	O
up	O
,	O
as	O
well	O
as	O
an	O
Apple	B-General_Concept
ID	I-General_Concept
.	O
</s>
<s>
Due	O
to	O
its	O
generality	O
,	O
Back	B-Operating_System
to	I-Operating_System
My	I-Operating_System
Mac	I-Operating_System
can	O
work	O
for	O
many	O
Bonjour-enabled	O
services	O
,	O
not	O
just	O
Screen	O
Sharing	O
(	O
similar	O
to	O
Apple	B-Operating_System
Remote	I-Operating_System
Desktop	I-Operating_System
)	O
and	O
File	O
Sharing	O
.	O
</s>
<s>
Users	O
must	O
have	O
a	O
router	O
that	O
supports	O
either	O
Universal	B-Application
Plug	I-Application
and	I-Application
Play	I-Application
(	O
UPnP	B-Application
)	O
or	O
NAT	B-Protocol
Port	I-Protocol
Mapping	I-Protocol
Protocol	I-Protocol
(	O
NAT-PMP	B-Protocol
)	O
with	O
either	O
of	O
those	O
features	O
enabled	O
in	O
their	O
connected	O
router	O
.	O
</s>
<s>
It	O
uses	O
UDP	O
port	O
4500	O
for	O
point-to-point	O
IPsec	B-Protocol
connections	O
(	O
which	O
may	O
be	O
mapped	O
to	O
different	O
UDP	O
ports	O
on	O
the	O
public	O
side	O
of	O
a	O
NAT	O
router	O
)	O
.	O
</s>
<s>
As	O
of	O
October	O
12	O
,	O
2011	O
,	O
Apple	O
has	O
included	O
Back	B-Operating_System
to	I-Operating_System
My	I-Operating_System
Mac	I-Operating_System
in	O
its	O
iCloud	B-Application
service	O
rather	O
than	O
the	O
previously	O
used	O
MobileMe	B-Application
,	O
thus	O
making	O
it	O
free	O
to	O
use	O
.	O
</s>
<s>
On	O
August	O
9	O
,	O
2018	O
,	O
Apple	O
updated	O
a	O
support	O
document	O
to	O
note	O
that	O
Back	B-Operating_System
to	I-Operating_System
My	I-Operating_System
Mac	I-Operating_System
would	O
not	O
be	O
part	O
of	O
the	O
macOS	B-Device
Mojave	I-Device
(	O
10.14	O
)	O
release	O
.	O
</s>
<s>
The	O
support	O
document	O
was	O
updated	O
again	O
on	O
May	O
31	O
,	O
2019	O
,	O
to	O
indicate	O
that	O
Back	B-Operating_System
to	I-Operating_System
My	I-Operating_System
Mac	I-Operating_System
services	O
would	O
be	O
discontinued	O
for	O
all	O
other	O
versions	O
of	O
macOS	O
as	O
of	O
July	O
1	O
,	O
2019	O
.	O
</s>
<s>
Back	B-Operating_System
to	I-Operating_System
My	I-Operating_System
Mac	I-Operating_System
can	O
be	O
used	O
to	O
edit	O
and	O
transfer	O
files	O
from	O
one	O
Mac	O
to	O
another	O
.	O
</s>
<s>
In	O
one	O
instance	O
an	O
Apple	O
Store	O
employee	O
used	O
this	O
technology	O
to	O
capture	O
the	O
image	O
of	O
a	O
person	O
who	O
stole	O
a	O
MacBook	B-Device
,	O
using	O
the	O
built	O
in	O
iSight	B-Protocol
webcam	O
.	O
</s>
